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Europhysics Letters (EPL)

Optical Bistability with Small Numbers of Atoms

Sarben Sarkar, J.S. Satchell

Published Apr 1, 1987• 25 citations
Publisher

Abstract

The master equation for optical bistability in the bad cavity limit is solved directly when the number of atoms is small. A necessary condition for bistability is given. In contrast to the semi-classical analysis, there is no sense in which there is bistability for 4 atoms; rather the order of 12 atoms is needed.
DOI
10.1209/0295-5075/3/7/005

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In a theoretical discussion of optical bistability, it is often necessary to resort to some approximation scheme to discuss time-dependent properties. The standard method consists in assuming a very good cavity (κ«γ⊥, γ11) Or a very bad cavity (γ11 <<κ1, γ⊥ ) and to perform an adiabatic elimihation of the fast varying variables. In the good cavity limit /1/ the atomic variables are eliminated and one is left with an equation for the field. In the bad cavity limit /2/ the field and the atomic polarization are eliminated and one is left with an eouation for the atomic inversion.
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